Conventionally, a sliding bearing that peripheral ends of a pair of semicircular half bearings are contacted to each other so as to be formed cylindrically is known (Patent Literature 1). In the case of manufacturing such a sliding bearing, a flat-plate material is deformed semicircular by press shaping, and subsequently, end surfaces of both axial ends and both peripheral ends of the semicircular material are cut so that a lateral width of the half bearing is made uniform and so-called finishing processing is performed.